Mechanical pencil of the screw feed type



D- 1949 J. 'r. BRUBAKER ,4

MECHANICAL PENCIL OF THE SCREW FEED TYPE Filed Sept. 21, 1944 V :5Shets-Sheet 1 INVENTOR, JOHN TEE'UEHKEKI Dec. 27, 1949 3, BAKE 2,492,838

MECHANICAL PENCIL OF THE SCREW FEED TYPE Filed Sept. 21,,1944 3Sheets-Sheet 2 INVENTOR I 1515 JOH/YTEfl/ZAKEIQ Dec. 27, 1949 J. T.BRUBAKER MECHANICAL PENCIL OF'THE SCREW FEED TYPE Filed Sept. 21, 1944 3Sheets-Sheet 3 Patented Dec. 27, 1949 MECHANICAL PENCILOF THE SCREW FEEDTYPE John T. Brubaker, Luray, Va.

Application September 21, 1944, Serial No. 555,139

18 Claims. (01. 120-18) This invention relates to a mechanical pencil ofthe screw-feed type.

A prime object is to provide an article of this character having novelmeans to grip the lead and feed it b rotation of a, tubular propellerthrough which the lead is fed by the gripping means which engages thelead at one or more slots in the tubular propeller.

A second object is to provide a novel expansible and contractile gripperstructure operable to release the lead when necessary for re-filling.

Another object is to provide the pencil with a novel slide havinggripper means swiveled thereon and engageable with the lead at one Ormore slots in a rotatable propeller tube, and which gripper means isexpansible and contractile in combination with camming means to move thesame to lead-releasing position.

Still another object is to provide novel nonrotary means to support thelead without contact with the barrel, engageable and disengageable withthe lead under control of an independently adjustable lead-feed tube.

A furtherobject is to provide a novel means to hold the lead inprojected position against danger of accidental receding.

The more specific objects and advantages will become apparent from aconsideration of the description following, taken in connection with theaccompanying drawings illustrating operative embodiments by way ofexample.

In said drawings:

Fig. 1 is a view through one form of the improved pencil takenapproximately centrally and longitudinally;

Fig. 2 is a perspective view showing the novel slidable nut andlead-gripper means swiveled thereon; v

Fig. 3 is a cross-section taken on the line 3'-3 of Fig. 1;

Fig. 4 is a central longitudinal sectional view taken through a modifiedform of the pencil;

Fig. 5 is a horizontal section taken on the line 55 of Fig. 4;

Fig. 6 is a perspective view of the jaw-separating spring employed inthe form ofFig. 4;

Fig. '7 is a substantially central longitudinal sectional View through afurther modified form of pencil;

Fig. 8 is a cross-sectional view taken. on the line 8--8 of Fig. '7;

Fig. 9 is a fragmentary elevation of the lower portion of the leadpropeller used in Fig. 7;

Fig. 10 is a perspective view of that portion of the lead propellershown in Fig. 9;

Fig. 11 is a perspective view of the lead supporting jaws;

Fig. 12 is a view of another modified form of pencil, being partly inelevation and partly in section taken approximately centrally andlongitudinally;

Fig. 13 is a cross-section taken on the line I3-l3 of Fig. 12;

Fig. 14 is a cross-section taken on the line l4l4 of Fig. 12;

Fig. 15 is a fragmentary sectional view of a modified form of leadgripper or feed jaw;

Fig. 16 is a view partly in elevation and partly in approximatelongitudinal section through a final modified form of pencil;

Fig. 17 is a longitudinal central sectional view taken at a right-angleto Fig. 16;

Fig. 18 is a cross-section taken on the line |B|8 of Fig. 17; and

Fig. 19 is a cross-section taken on the line l9-l 9 of Fig. 16.

Referring specifically to the drawings wherein the same referencecharacters designate the same or similar parts through the differentviews, and first to the form of Figs. 1 to 3, the improved pencil has abarrel or casing at I0, open at the top and at the lower end, preferablyhaving a tapered portion II as shown open at the apex so that the leador marker I2 may project therethrough.

Detachably screw-threaded in the top of the barrel at 13 is a tubularbearing in the form of a plug M. It will be noted that such plug abovethe screw-threads l3 engages the inner wall of the barrel along a plainsurface l5 of any desired extent. This cap is provided with a resilientclip [6, whereby the pencil may be detachably engaged with a pocket ofan article of clothing, or other support.

A lead propeller or feed tube is generally designated l1, and locatedcentrally and longitudinally of the barrel. This feed tube is preferablymade in a single piece, and at the upper end has a journal [8 rotatablymounted in the bore of the plug M as a bearing. A knob or any equivalentIQ is threaded or otherwise attached at 20 to the journal l8, and it isadapted to be peripherially manually gripped in order to rotate the feedtube I! in either direction. The feed tube is held against accidentallongitudinal displacement relatively to the bearing I l since it has ashoulder 20 engaging the under surface of the latter in opposition tothe knob 19, such shoulder being formed at the larger end of a cone 2|.

The lead 12 is fed or supplied to the tube l1 23 has a neck or extension26, on which a ring 7 2'! is swiveled, and with which. it isinterengaged may be in any desired lengths and it is propelled or fedthrough the bore or central opening of the feed tube IT by successiverotations of the knob IS according to the extent which the lower end ofthe lead abrades or wears. Through such rotation of the knob [9 in onedirection, tube I! will be turned so that its screw-threads 35 throughinterengagement with those at 35 will move the slide 23 as suggested inthe dotted line position of Fig. 1, during which action, the

. lead will be gripped by the jaws 32 since the reat an annular groove28 in the extension and an...

annular rib 29 on the ring. This ring constitutes part of a grippergenerally designated 38, and which is completed by.one or moreresilientarms 3|. Each arm adjacent its" distal end has a lead gripping jaw 32,which optionally may be serrated or roughened as at 33 to increase itsdegree of engagement withthe lead I2.

Said feed tube I1 has a pair of diametrically opposite longitudinalslots 34 therethrough, although one slot and one arm and jaw 3I-32 willsuffice in most instances, in which the jaws 32 are positioned to slide.The feed tube H has external screw-threads at 35 which are engaged bythe screw-threads 3B in the bore of the nut or slide 23.

Extensions or fingers 31 rise from the jaws 32 and are engageable withthe exterior surface of the cone 2|:and forcedat the upper extreme ofmovement of the feeding device 38 to release the lead preparatory to itsbeing replenished.

Located within the tapered portion II of the barrel is a pair of holdingjaws 38 adapted at their facing surfaces to contact directly the leadI2, as shown in Figs. 1 and 5. The upper or larger ends of jaws 38 areengaged by a disk or plate 39, rigid on or integral with and formingpart of the feed tube I'I. These jaws 38 may be independent of the feedtube, but as shown they are preferably interconnected therewith as bymeans of pins 40, rising one from each jaw, occupying diametricallyarranged slots M in the disk 39 and being held against detachmenttherefrom by heads 42 on the pins 40.

The construction described is such that all parts as a unit are slidablyremovable from and replaceable into the barrel I0 through the detachmentof plug or tube I4 at the screw-threads I3, it being clear that the jaws38 will be withdrawn with the feed tube H in view of the interconnectiontherewith at the pins 40, and notwithstanding the presence of the ribs25, since the slots 4| may be registered therewith and slidably receivethe same.

In the use of the pencil, it is to be observed that the jaws 38 projectbelow the portion -II of the barrel so that thelea'd-will be supportedby the jaws and cannot contact the barrel which is a cause of frequentfracture of lead in existing constructions. Also the degree of pressurewhich the jaws 38 have on the lead may be regulated by the longitudinalposition of the feed tube II governed by the adjustment or position ofthe plug I4, which correspondin lv presses the disk 3.! against theupper ends of the jaws or recedes therefrom to enable the jaws'toseparateby upward movement-along the'inclined surfaces of the taperedportion 1 I It will be'clear that the parts are so proportioned .as toaccommodate lead of various diameters or thicknesses. it being realizedthat the differences in the diameters usually is in thousandths of aninch.

Further, with respect to operation, the lead I2 silient arms 3I arebiased to contract or move toward each other. However, when the lead isworn, and needs replenishing, knob I9 is turned in the retrogradedirection to move the feeding device 22 upwardly to the full lineposition of Fig. 1, during which movement the fingers contact the cam orcone 2| and separate the jaws 22 and thus release the used or shortlength'of lead. Such separation of the jaws need merely be a matter of athousandth or a few thousandths of an inch. When the jaws are thusseparated, a new length of lead I2 is supplied to the pencil and theknob I9 slightly turned in the opposite direction so that the jaws undertheir bias will grip the. lead which may thereafter be fed through theoperation of the pencil as described.

Referring now to Figs. 4 to 6, wherein a modified form of lead holdingjaws is shown, the lead is heldin writing position and against recessiontherefrom by a plurality of jaws functioning generally likethose at 38and designated 41. Jaws 41 extend below the barrel as in the first formof the invention for the same purpose, and the surfaces thereof whichcontact and hold the lead 46 are serrated or otherwise roughened as at48. The upper outer edges of the jaws 41 are preferably'cut .away at 49to provide clearance for upward adjustment or variation of the positionof jaws 4'I.

When the feed tube recedes, the jaws 41 will separate and move upwardlyby reason of their contact with the tapered wall of the lower portion ofthe barrel and also by reason of the expansive or straightening actionof an arcuate spring 54 which is located in a recess 55 of one of thejaws 41, and which spring in its terminals has notches 56' of sufiicientsize to enable the lead 46 to be fed without contact with such spring54. It is to be understood that in all positions of the jaws 41 theserrations 48 will hold the lead against recession or retraction; and itis to be understood that these serrations and/or spring 54 may .be usedin the first form as well as all succeeding forms of the invention.

Another modified-form of the invention is disclosed in Figs. 7 to 11. Inthis form I use a barrel or casing I0 having a lower tapered end portionII.'. At the upper end, a tubular bearing I4 is screw-threaded as at I3having a resilient attaching clip I6 thereon. A pair of diametricallyopposite longitudinal ribs 25' are provided on th interior of the wallof. the barrel I0. 0perable centrally and disposed longitudinally withinbarrel IIIis a feedingtube structure generally designated 51, preferablyin a single piece. This structur includes a tubular journal I8 and thestructure 57 has a central longitudinal bore 58, through which the leadI 2' is supplied from above. An operating knob I9 is secured to theupper end of the journal I8 as at 20 in any suitable manner inopposition to a shoulder 20' formed at the upper end-of a conical cam2|. All parts described with primed numerals coratlases resp'ond inconstraction-and operation to the same- Tluineral's unprim'ed as used inthe first form.

The feed tube structure throughout most of itslengthhas a helical slot58, into which proeject one or more gripping-jaws 59, preferablyroughened or serrated at their inner ends at 60 for directengagementwith the 'lead l2. Jaws 59 arecarried by arms tl mounted in any suitablemanner-on'a slide 6i which have peripheral slots 62 interengaged w-iththe ribs '25 so that the slide cannot turn. The slide also has a bore orcentral opening as so that it may freely Islide 'along-the'tubestructured]. Jaws 59have spreading 'fingersii l to co-act withthe cam orcone 29' for the samereaction as is true between the fin- :"gers 37and-"cam 3| in the first form.

"The knob l 9' may beturned in either-direction to turn the feedingdevice 51 accordingly and through such turning, the 'interengagement of"the jaws 'orlgrippers'59 with the helical groove 58 'will move theslide Bl longitudinally of the barrel, the .jaws159 functioning like thejaws 32 of the first form, and in'addition functioning as a propellingmeans in view'of the interengagement of the grippers 59 with the helicalgroove or slot 58. 2

Movement of the arms St to the upper limit in Fig. 1causesfingerst'l totheir contact with the cone 2! to spread and release the lead. In thedotted line position of Fig. 7, the lead will be .gripped by the jawsBB-so as to be fed through rotation of the feed tube 51 and sliding ofelement 6!.

Tube 51 :and parts connected thereto may be removed and replacedas aunit like the generally corresponding parts in the other forms of theinventionThe tubezstructure 51in this form, however, has a plate or disk64, at its lower end in contact with the upper surfaces of gripping jaws'-'85'for the lead 12', the disk having slots 66 in its periphery forregistry with the ribs to enable removal thereover. The jaws 65 areloose within the tapered portion ll and function generally like those at38 and 41, being loose and gripping the lead 12 at theirfacing surfaces.Disk 64 has a bifurcated downward extension .forming generallytriangular tines 61 which are of less thickness than the lead 12' andwhich are disposed between the jaws 65. Th rotation of the feed tube-5lsince the tines B'lare rigid therewith, will also rotate the jaws 65.The adjustment of feed tube 1'51 at the threads 13 determine the degreeof gripping of jaws 65 against the lead, it being clear that oppositemovement of the feed tube 51 *will permit expansion of the jaws 65 toaccommodate thicker leads or leads of greater diameter.

Aiurther modified form is shown in Figs. 12 to 14-. This form of theinvention primarily differs from the first form in that a feeding device.22 generally similar to that employed at 22 is operable in a positioninverted with respect thereto, and with arms and jaws biased to ex-.pand rather than to contract. The barrel Hi conforms to that employedat IU, and'the bearing or'head M conforms to that at is, being, if

desired, the same as the latter and in screw-.

threaded attachment and adjustment at lfi with said barrel 19 Theattaching clip is designated 16- and the barrel has ribs.25 like thoseat 25. The lead .feed tube Il is generally like that employed at H,being rotatable at a journal l8 within the head M and rotatabl .ineither direction through the manipulation of a knob I9 screw-threaded orotherwise secured thereto.

ISaid knob Lil and a.pin or shoulder 2| attach tubal! to bearing I4 Saidfeed tube structure l'l has a liiskzat 39 -andall parts carried by thetube are detachable and replaceable-as a'unit as inthe other forms,'thedisk 39 having slots 68' for registration :with and sliding-overthel'ibs 25 Depending from the disk 39 is a split holder tube :69,' thesame having one or more longitudinal slits asshown. 'The'lead feed tubei-l has a central longitudinal bore or opening, through which the lead10 supplied from the top. The slit or slits at :H Sin tube 69, enablethe tube to be contracted about different sizes of lead10,'accordingto'the.adjustment of jaws i2, and between whicha-holdertube "SS-eXtends-and which jaws are engaged at thei-r upper orlarger ends by the disk 39 and are housed within a lower conical portionil 'of the 'barrel ll), the holder tube 69 extending below the barrel-soas to support the lead withoutzcontact with the latter. The position ofthe jaws "l2 isgovernedbytheadjustment of theplug M at'th'escrew-threads13 Althoughl'ha've shown a different means 'for holding engagement withthe lead at the lower end of the pencil, .inithis form, it is to beunderstood that I may :lnterchangeably use such lead holding means atthe lower end as is shown many of the other forms of the invention."This is true not only .in this modified form, but-in'all otherforms.

Reverting to the leadfeed device22', the-same has a nut-23 inscrew-threaded engagementwith the exterior screw-threads of the feedtube slil tit-"35 such nut being slidable butnon-rotatable in view ofthe interengagement of slot'sizid 'with the ribs 25 Swiveled on anextension 26* of nut 23* in the same manner'as between the nut -23and'ring 27 in the first :form is a ring 21 from which depend resilientarmsS l 'biased to expand or separate at lead-gripping members orjaws32, which extend through diametrically opposite slots 34 in the feedtube if! to mountislidably but non-rotatably the feed device 22'. Whenthis device 22' is practically in its uppermost position, the jaws t2expand into an annular groove 13 provided in the inner surface of thebarrel Hi. It will be noted that the outer portions of the jaws as at 14present rounded noses, so that the jaws extend into the groove torelease short lengths of lead. The'device 2| ismoved in either directionaccording to the direction of turning of knob 19 and when the noses 14move out of the groove 13 they are moved or compressed toward each otherby th :wall defining groove 13 which thus functions as a cam. The jawswill thus .feed or move the lead longitudinally of the feeder device l1according to the operation of the latter. In Fig. 12, the jaws are'shownin. full .linesin the lead-releasing or expanded position, while indotted linessuch device--22' .is shown in the leadgripping and feeding'condition.

Referring now to the final modified form of Figs. 16 to 19, itembodiesthe'same generalprinciples as the preceding forms, but the feeding.movement of the parts is greatly shortened. In

this form, the barrel is shown at I0 and at its lower end has aconicalor tapered portion ll while at the upper end it is closed by a bearingmember M screw-threaded as at 13* into the casing or barrel l0 Aresilient attaching clip -liiextends from the-bearing I4".

Journaledin the bearing HI is a lead feed tube ll having acentrallongitudinal bore ll through which the lead .lz issupplied fromabove and fed.

Retained in the conical portion li are lead .grippingjaws or segments'38), adapted attheir 'flatsurfaces to engage saidlead 12 .Said jaws attheir flat surfaces may be plain, but are preferably serrated orroughened as at 38 in order to hold the lead l2 against retraction orrecession into the barrel, but capable of extension slidably through andbeyond the jaws 38 as required as the lead wears. It will be noted thatsuch jaws extend outwardly beyond the barrel so as to support the leaddirectly without contact thereof against the barrel. Such serrations orteeth at 38 preferably provide horizontal shoulders 38 and upwardly andoutwardly inclined surfaces 38 connecting them.

Tube W is held in the bearing [4 against longitudinal movement by meansof a pin or shoulder 2 l engaging the inner end of the latter, and bymeans of a knob 20 engaging the outer end of the latter, such knob beingscrew-threaded to tube H as in the preceding forms or attached in anyother desired manner. At the inner end, tube ll has a disk or head 39engaged with the upper ends of the jaws 38 so as to give the requisitepressure against the latter to clamp the lead l2, according to its size,it being clear that through turning of the bearing M that the feed tubell will be longitudinally adjusted according to the position desired forsaid jaws 38 dependent on the size of the lead I2". Disk 39 is providedwith radial peripheral slots 4 l to enable the feed tube and all partscarried thereby to be removed and replaced as a unit, such slots 4|enabling passage over relatively short diagrammatically opposite ribs 25carried on the inner wall of barrel lll Said feed tube ll to a limitedextent has screw-threads 35 provided thereon, and on which a nut 23 isscrew-threaded at its bore. This nut has slots 24 corresponding to thoseat 4 l interengaged with the ribs 25 so that the nut cannot turnalthough it will slide through rotation of feed tube IT A ring 21 isswiveled on an extension or neck 26 in the same manner that the ring 21is swiveled on the nut 23. This ring 21 has one or more resilient jawsor grippers 3| depending therefrom and extending through the slots 34'provided diametrically in the feed tube ll Such jaws optionally serratedat 33 and are biased or function to grip the lead l2 in order that thelead may be positively fed through the rotation of the knob 20 whichwill turn the feed tube li and cause sliding of the nut 23, ring 21 andthe jaws or grippers. It will also be noted that the lower end walls atthe slots 34 are inclined at 3'! so that adjacent the lower extremity ofmovement of the jaws, they will be automatically separated through theturning of the knob 20 and feed tube to release the lead, although thelead cannot recede due to its engagement by the teeth 38. With the jawseither separated or at their uppermost limit of movement, a new lead maybe pushed down the feed tube until it is frictionally gripped by theteeth 38 above the short length of lead remaining between jaws 38 andthereafter jaws 33 may be fed downwardly to correspondingly feed the newlead against said short length of lead through the turning of the knob29.

It will be noted that in this final form of the invention, successiverelatively short feed movements for the lead are provided. Such aconstruction considerably reduces manufacturing costs.

In all forms of the invention, in lieu of the various jaws or grippersdescribed, such as those at 3|, I may use the modified form disclosed inFig. 15. In this modified form, each arm isiiesiliefit such as that at3| which corresponds to that at 31. For instance, this arm may be biasedto contract or expand according to the form of the invention in which itis used, and it has a surface at 33 to engage the side of a lead such asl2, which surface may optionally be plain or serrated. This arm 3 I hasa lug or flange 15 which will overlap the upper end of the lead in orderto provide a shoulder to push against it in addition to the frictionalgripping of the side of the lead by the wall 33.

Attention is called to the fact that in all forms of the invention, thevarious parts are adapted for interchanging or each form is adapted tobe modified or re-built embodying the parts and principles of theothers. In addition, the parts may be made of any suitable materials,particularly metal, plastics or the like or be composite.

I claim as my invention:

1. A pencil having a barrel, a rotatable lead feed tube disposed withinand longitudinally of the barrel, said tube having its bore opening atthe top for supply of lead from the exterior of the pencil, a slidewithin the barrel, coacting means on the slide and the tube to move theslide along the tube through rotation of the latter, means to hold theslide from rotation relatively to the barrel, said tube having a slot,and the lastmentioned means being positioned through the slot forfeeding engagement with lead in the barrel.

2. A pencil having a barrel, a rotatable lead feed tube disposed withinand longitudinally of the barrel, said tube having its bore opening atthe top for supply of lead from the exterior of the pencil, a slidewithin the barrel, coacting means on the slide and the tube to move theslide along the tube through rotation of the latter, means to hold theslide from rotation relatively to the barrel, said tube having a slot,the lastmentioned means being positioned through the slot for feedingengagement with lead in the barrel, and means against which thelast-mentioned means is operable to impart a lead-releasing movement tothe latter.

3. A pencil having a barrel, a rotatable lead feed tube disposed withinand longitudinally of the barrel, a slide within the barrel, coactingmeans on the slide and the tube to move the slide along the tube throughrotation of the latter, means to hold the slide from rotation relativelyto the barrel, said tube having its bore opening at the top for supplyof lead from the exterior of the pencil, said tube having a slot, thelast-mentioned means being positioned through the slot for feedingengagement with lead in the barrel, a cam surface on one of the parts,and the last-mentioned means being movable against the cam means toimpart a lead-releasing movement thereto.

4. A pencil having a barrel, a, rotatable lead feed tube disposed withinand longitudinally of the barrel, a slide within the barrel, coactingmeans on the slide and the tube to move the slide along the tube throughrotation of the latter, means to hold the slide from rotation relativelyto the barrel, said tube having a slot, the lastmentioned means beingpositioned through the slot for feeding engagement with lead inthebarrel, a bearing in the barrel journaling and carrying said tube, jawmeans to grip the lead at L menses 5. .A pencil having a barrel, :arotatable lead feed tube disposed within and longitudinally of thebarrel, a .slide within said barrel having a lead gripping jaw thereon,means to :hold the slide from rotation relatively to the barrel, saidfeed tubehaving 'a helical slot;said jaw extending into the slot andbeing positioned to function dually to :grip and'feedlead passingtherethrough and to follow the helical slot.

6. A pencil having a barrel, .arotatable lead feed tube disposed withinand longitudinally of the barrel, .a slide within said barrel having alead gripping jaw thereon, means to hold the slide from rotationrelatively to'the barrel, said 'feed tube having ahelical slot, said jawextending into the slot and being positioned to function dually to gripand feed lead passing therethrough and to follow the helical -s1ot,'acam pn'said feed tube, and said jaw being movable against said cam forlead releasing movement.

7. Apencil having a barrel member, a rotatable lead feed tube memberdisposed within and longitudinally thereof, a slide within the barrelmember, coacting means between the slide and the tube member to move theslide along the tube member through the rotation of the latter, means tohold the slide from rotation relatively to the barrel, said tube memberbeing slotted, means on the slide to grip and release lead for feedingmovements, a cam on said feed tube, and said second-mentioned meansbeing biased to move to lead-releasing position when engaging said cam.

8. A pencil having a barrel member, a' lead 'feed tube disposed withinand longitudinally "thereof, a slide within the barrel means to hold theslide against rotation with respect thereto, a jaw on said slide, saidtube having a helical slot therethrough, and said jaw extending throughsaid slot functioning dually to grip and feed lead and to follow saidslot to "impart feeding movement to the lead.

9. A pencil having a barrel member, a rotatable lead feed tube memberdisposed within and long'itudinally thereof, a slide within the barrelmember means to hold the slide against rotation relatively the barrelmember, a swivel attached to said slide. inter-engaging screw-threads onthe tube member and slide said tube member having a slot. and a jawmember on the swivel extending into the slot and engageable with leadtherein to feed the same.

10. A pencil having a barrel member, a rotatable lead feed tube memberdisposed within and longitudinally thereof, a slide within the barrelmember means to hold the slide against rotation relatively the barrelmember, a swivel attached to said slide, inter-engaging screw-threads onthe tube member and slide said tube member having a slot, a jaw memberon the swivel extending into the slot and engageable with lead thereinto feed the same, jaw means at the writing end of the barrel havingcamming engagement with the latter for movement into contact with lead,and means to adjust the position of the tube mem} ber relatively to thejaw means to control the position of the latter and its degree ofgripping engagement with lead.

11. A pencil having a barrel member, a rotatable lead feed tube memberdisposed within and longitudinally thereof, a slide within the barrelmember means to hold the slide against rotation relatively thereto, aswivel attached to said slide, inter-engaging screw-threads on the tubemember and slide, said tube member having a slot, 2.

did

jaw memberro'n the swivel extending into the slot and engageable withlead "therein to feed the same, jaw means atthe writing and of thebarrel having camming engagement with the latter for movement intocontact with lead, means to adjust the position vof the tube memberrelatively to the jaw means to control the position =of the lattelandits degree "of gripping engagement with lead,and means interconnectingthe tube member and jaw means FfOl' movement of the latter nnitarilywith the tube member and for spreading movement.

12. Aipencil having :a barrel member, a-rotatablelead feed tube memberdisposed within and longitudinally thereof, a slide within the barrelmember means to hold the slide against rotation relatively the "barrelmember, a swivel attached tosa'id slide, inter-engaging screw-threa'ds-'on the tube member and slide said tube member having a slot, a jawmember .on the swivel extending into the slotand engageablewith leadtherein to "feed the same, said jaw member being resilient, a cam onthe-tube memberfand -means on the jaw member engageablewith the camadjacent one extremity of movement of the swivel to move the jaw memberto lead releasing position.

18. A pencil-having a barrel, a rotatable lead feed tube disposed withinand longitudinally thereof, a bearing screw-threaded in the upper end ofthe barrel "foradjustment, said'tube being journalled in said bearing,and extending exteriorly thereof so that it may be gripped for manualoperation, said barrel having an internal longitudinallyextendingspline, a nut in screw-threaded "engagement with 'the tube having a slot'interengagedwiththe spline, a ringhaving a flange attaching andswiveling it on the nut, a pair of opposed lead gripping jaws extendingfrom the ring, said tube having oppositely aligned slots, said jawsextending into :said slots for gripping engagement with lead therein.

14. A pencil having a barrel, a rotatable lead feed tube disposed withinand longitudinally thereof, a bearing screw-threaded in the upper end ofthe barrel for adjustment, said tube being journalled in said bearing,and extending exteriorly thereof so that it may be gripped for manualoperation, said barrel having an internal longitudinally extendingspline, a nut in screwthreaded engagement with the tube having a slotinterengaged with the spline, a ring having a flange attaching andswiveling it on the nut, a pair of opposed lead gripping jaws extendingfrom the ring, said tube having oppositely aligned slots, said jawsextending into said slots for gripping engagement with lead therein, adisk at the lower end of said tube, lead gripping jaws at the writingend of the barrel engaging the latter along upwardly inclined surfaces,said disk having inwardly extending slots, the last-mentioned jawshaving studs retained by the disk and slidably movable in said slots,one of said slots also functioning to clear said spline to enableremoval of all parts with the tube as a unit.

to hold said slide against rotation relatively to the barrel, jawsextending from the slide having portions entering said slot functioningdually to follow the same to cause the nut to slide and to grip the leadbetween them, said jaws being resilient and adapted to contact said camadjacent one extremity of movement to separate the jaws to release thelead.

16. A pencil having a barrel, a bearing adjustably screw-threaded in theupper end thereof, a

lead feed tube rotatably mounted in said bearing and disposed within andlongitudinally of the barrel, an operating element on the tube engagingthe outer end of the bearing, said tube having a cam provided with ashoulder engaging the inner end of the bearing, said tube having ahelical slot therethrough, a slide surrounding the tube. means to holdsaid slide against rotation relatively to the barrel, jaws extendingfrom the slide having portions entering said slot functioning dually tofollow the same to cause the nut to slide and to grip the lead betweenthem, said jaws being resilient and adapted to contact said cam adjacentone extremity of movement to separate the jaws to release the lead, adisk at the lower end of the tube, jaws to grip the lead at the lowerend of the tube disposed within the latter and engaging the same alonginclined surfaces, said jaws being engageable at their upper ends bysaid disk, and said tube having a bifurcated downward extension disposedbetween the 12 of the barrel having a concavity, and said jaw beingresilient and normally tending to move into said concavity inlead-releasing position.

18. A pencil having a barrel, a lead feed tube rotatable therein anddisposed longitudinally thereof, a nut threaded on said tube, meansholding said nut against rotation relatively to the barrel, a swivelattached to said nut having a jaw, said tube having a longitudinallyextending slot through which a portion of the jaw projects for feedingcontact with lead therein, the inner wall of the barrel having aconcavity, and said jaw being resilient and normally tending to moveinto said cavity in lead-releasing position, said tube having anextension at the writing end of the pencil through which the leadextends, said extension being split, and means engagin the extension andbarrel under control of the tube to regulate the contraction of theextension with respect to the lead therein.

JOHN T. BRUBAKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 271,926 Schrag Feb. 6, 1883845,422 Schmitz Jan. 4, 1910 1,552,638 Nelson Sept. 8, 1925 1,575,195Fleming Mar. 2, 1926 1,621,990 Lippert et a1 Mar. 22, 1927 1,908,491Steiger May 9, 1933 1,967,484 Stenerson July 24, 1934 FOREIGN PATENTSNumber Country Date 3,061 Great Britain July 13, 1881

